Automatic telephone system



March 10, 1931. M. MATHIAS 1,795,209

AUTOMATIC TELEPHONE SYSTEM Filed Aug. 27. 1927 s Sheets-Sheet 1 maximili an NEH-Lia 5 March 10,1931. M. MATHIAS AUTOMATIC TELEPHONE SYSTEM Filed Aug. 27, 1927 3 Sheets-Sheet 2 j nueniur' f'qammflian MaT hias H777 WM March 10, 1931. M. MATHIAS AUTOMATIC TELEPHONE SYSTEM 3 Shets-Sheet 3 Filed Aug. 27, 1927 1m Maximilian Ma Z'hias Patented Mar. 10, 1931 UNITED STATES PATENT OFFICE MAXIMILIAN MATHIAS, 0F BERLIN, GERMANY, ASSIGNOR TO SIEMENS 8t EALSKE AKTIENGESELLSCH'AFT, 0F WERNERWERK, SIEMENSSTADT, NEAR BERLIN, GER- MANY Application filed'August 27, 1927, Serial No. 215,859, and in Germany September 15, 1926.

This invention relates totelephone sysent ways according to the number of initial impulses received before the positioning impulsesare received. Y c

The steering of the connecting devices by the. initial impulses takes up a certain amount of time, and it may happen that the first positioning impulse is transmitted before this steering has been completed, and this may cause traificv-disturbances of wrong connections. V, i g r The object of this'inventionis to remove these difficulties, this beinghchievedin' a sim 1e manner in that-an impulse repeater located at theoutgoing end of the junction line is provided with a relay device, which is under the control of positioning impulses and causes the impulse recelvlng relay to function only after one or more impulses have been received andafter the train of im pulses have ended it causes the repeater relay to transmit a corresponding number of additional impulses. V v

r The figures show by way of example a circuitfor. setting up local and trunk calls over atwo-wire junction. line and the; same final selector. .1

The Fig. 1 shows a subscribers station N1, which can be connected over a preselector VVV to the group selector, GW, to the bank contacts of which is connected over a repeater U6 1 the outgoing end of two-wirejunction lines. This repeater U6 1 can also be reached over a preselector FVVV for setting up trunk calls. Thepreselector FVNV is connected to ajack FKZ located at the; trunk position FPZ. The incoming end of the twowire junction line terminates at a repeater U6 2, which is shown in Figure 2and has associated with it afinal selector LW, Fig. 8, for local and trunk calls. I

The general method of operating this arrangement will now be described.

When a subscriber takes intouse the repeater Ue 1 at the outgoing end of a twowire junction line VL, an initial impulse is transmittedover the junction line VL; thereby the switching devices embraced in the repeater U6 2 are so affected that they steer the final selector when a local connection is set up. hen, however, the trunk position FPZ has been connected to the repeater Us 1, then two initial impulses are transmitted over the junction line VL before the positioning impulses, and the devices at the. repeater U6 2 at the incoming end of the junction line VL are caused to steer the final selector for setting up a trunk connection.

A description will now be given of the; method of operating the circuits shown in the accompanying drawings when a local call and a trunk call are set up. For this purpose it will be assumed that the subscribers station N 1 indicated in Fig. 1 wishes to set; up a connection with a subscriber, who can be reached over the final selector LW shown in Figure 3. When the receiver is taken down, the connecting devices, which precede the repeater Ue 1, are taken into use in,

peater U6 1 is the first free one in that level,-

the following circuit is established: earth at 'the group selector GW, back contacts 9 f, 34

0 1, 11 h, 21 'n, winding of relay X, battery, earth. The relay X is energized and switches over its contacts. At the contacts 22 m and 23 00 the source of alternating current VVQ, is applied to the left hand windings of the repeater 24 in the junction line VL, thereby energizing over the leads La and Lb the alternating current relay J 2 in Figure 2 at the incoming end of the junction line. At contact 5m the relay CZ (winding-I) is energized, at 35 Cl it closes a locking circuit for its second winding, at the change-over contact 36 c 1 the upper speaking lead is switched through to the winding of the impulse receiving relay A 1 and at 3 1 a 1 is opened the circuit of the relay X, which now discon- Thus only a short'impulse is transmittedover the junction line VL to the repeater Ue 2. The relay E is energized over the contacts 38 c 1 and 6 00,-an'd it locks itselfover its If the subscriber now dials the second digit, 10 the relay'A 1 is energized by the firstcurrent impulse over: earth at the preceding connecting device, a-lead, front contact 36 c 1, back contacts 32 2' 1, 33 p 1, winding of relay A 1, battery, earth. The relay A '1 switches I over its contact 13 a 1, thereby closing the following circuit for the relay U; earth, front contact 13 a 1, back contact 18 m, winding I of relay U, resistance W 1, battery, earth.

The relay Uactuates its contact 16 a and =1 20 after relay A falls back the relay -M'is ener gized 'in the following circuit: earth,'-fro'nt contact 16 u, windingI ofirelay M, winding I of relay U, resistance W 1, battery, earth. The winding I of relay'U is shortcircuited at contactlS m and "at the same time the short circuit is removed from thewinding II of relay 'Ufso that the relay U're'mains fenergizedrover; its second winding and the commas a l as relay A1 responds tothe impulses. The relays U and-M maintain themselves energized during the impulse transmission The relays are so connected "that the contact 12 a lz'has already fallen back'when the contact 22 m is actuated, The

. relay M switchesover its contact 22 m, hence during the subsequent number impulses the relay X is' operated each" time the relay. A is energized The relay X is energized over: earth, impulse contact '12 a 1,.front contacts 22 m, 21%, winding of relay X, battery, earth. The contacts 22 w and 23 w repeat the impulses to the. repeater U0 2. After; the last impulse when the contact 130! 1 has fallen back, the relay Uis first deenergized. Relay M is a slowacting relay and falls back later, thus the relay X is again energized. over:

earth, back contact 23 a, front contacts 22 m,21 a, winding of relay X, battery, earth. The repeatedimpulsesoperate repeater U6 2 and final selector Ll/V in known manner.

In order to release the connecting devices it is necessary to transmit a'comparatively long alternating current impulsefroin the source of alternating-current VVQ at the repeaterUel to the alternating current relay J 2 attherepeater U6 2.

The circuit of the relay C 1' at-the repeater Ue 1 was interrupted at the group selector. The relay C 1 falls back and at its contact 37 c1 itcloses a circuit for energizing the relay M (winding II), which actuates its con.- tact 22 m and thereby establishes a circuit for the relay earth, back contact 23 a, front contacts 22 m and 21 a, winding of relay X, battery, earth. Relay X at its chi;

E, battery, 'locks itself, and it alsofs'witches over the con- 115 tacts 22 a: and 23 00 connects the source of alternating current WQ, to the junction line VL, and after a comparatively long time the circuit of relay X is opened at contact 21 n, because the relay N has locked itself over earth, front contacts 5 00 and 1 e. The circuit. of relay X is not interrupted until relay E, which is slow to release, has opened this looking circuit at'contact 1 e andthe relay N has fallen back after a little delay.

A descriptionwill now be given ofthe setting up of a trunk call over the junction line VL to a subscriber connected to the final selector LW in Fig, 3. The'wanted subscribers number is given to the operator at the trunkposition FPZ in any desired manner. Theoperator throws the diallingswitch and inserts the plug St into an 'idle jack'FKZ. The preselector FVW connected to this jack hunts for an idle repeater U6 1 connected to a; junction line outgoing in'the required direction. The throwing of the dialling switch connects battery at contact a lover the contact springs 102, 103 andlOt', lead 110,plug

St, jack FKZ, upper wiper of FVW and over? contact '36 c 1' tothe winding I of relay F.

Relay F operates and at contact 9 f removes the shortcircuit from its winding II, so that this is energized in series with relayXoverthe cut off relay of F VW. v5 Relay X' at its con-*' 95. tacts 22 'w and 23 w ap'pliesthesource of alternating current 'W@ to the lefthand wind- "ings of repeater 24 of the junctionline VL, thereby energizing over the leads La and L6 the alternating current reIay J 2in Fig. 2 at the incoming end of the unction line. Relay '0 1 is energized over contact5 w, and over contact 35 c 1 it closes a locking circuit'for its secondwinding and thewinding II'of'relay F. At thech'ange-over,contact 36 0 1 it switches the upper speaking lead through to the winding of the impulse receiving relay A 1 and at contact 34 '01 it opens the circuit of relay X, which at contacts22m and 23 in now disconnects the source of alternating current from the junction line (first initial-impulse) Relay E i's energi'zedover earth, 'frontcontact 38 c 1, backcontact 6 m, winding'jofrelay earth. JAt contact 36 the relay tacts 1 e and 2 e: over the latterthe relay X is energized a second time over earth, front contacts 2 e, 10 f, back contact 21 a, winding of relay X, battery, earth. Over earth, front contacts 5 w, 1 e, winding of relay N, battery, earth, the relay N is energized and at contact 21' n it opens the circuit of relay X. Thereby a second initial impulse is sent by the contacts 22 w and 23 w from the alternating current source WQ over the junction line to the alternating current relay J 2 at the incoming end of the junction line. Relay N'locks it self at contact 13 n over earth, front contacts 38 c 1, 13 a, winding of relay N, battery, earth. When the'trunk operator then dials,'the same 129 operations take place as above described for a local call. The further setting up. of the connection as far as initiating the testing is completed 1n known manner.

To Initiate the testing, the operator throws the test key PS. Thereby battery is applied over the key PS, contact springs 1 11 and 104 a of the key PS, leads 110, 111, jack spring 112,

upper Wiper of F VW, contacts 36 o 1, 32 z 1, 135 p 1, to the. Winding of relay G, the other end of which is connected to earth. over the contacts; 14. m, 10 f and 2 e. Relay G is operated in this circuit and at contact 7 g closes a. so

the, operating circuit of the relay M (winding II). Relay X is now operated over: earth, back contact 23 u, front contacts 22 m and 21 n, Winding of relay X, battery, earth. At contacts; 2200211101 23 a the alternating current source WQ isconnected to the junction line VL. But relay M at the same'time at contacts 145 m opensthe circuit of relay G, which at contact 7 9 opens the circuit of relay M. The latter f'alls'back slowly and at its contact 22 m it releases the relay X. The alternatingcurrent source VVQ is again'connected up at thev contacts 22% and'23 00. Hence a short impulse is sent'over the junction line to initiate. the testing. Other testing operations and the release of the connection takes place means for preventing the digit impulses from being eflective prior to the transmission of the preliminary impulse.

2.v In a telephone system, a trunk line,

meansfor establishing connection to said trunk line, means responsive to the establishment of the connection for transmitting a preliminary impulse over said trunk line, means for transmitting a group of digit impulses over the established connection, and means for preventing the digit impulses from being effective prior to the transmission of the preliminary impulse, said last named means including means. for rendering the first digit impulse ineffective and for producing an additional impulse after the last digit impulse has; been transmitted. V

8 Ina telephone system, an impulse repeater including animpulse receiving relay an impulse repeating relay, means for transmitting a group of digit impulses to the receiving relay, and means responsive to the first impulse transmittedfor preparing said repeating relay to repeat the, subsequent impulses and to transmit an additionalimpulse responsive tothe cessation of the impulses transmitted to the receiving relay.

a. In a telephone-system, an impulse repeater including an impulse repeating relay and a relay device, means. for transmitting a group of digit: impulses to the repeater, and means responsive to the first impulse received for rendering said impulse relay controllable by subsequent impulsesand for conditioning the relay device so that the impulse repeating relay shall repeat the subsequent digit. impulses and then an impulse corresponding to the first impulse received.

5. In a telephone system, an impulse repeater including an impulse repeating relay and av relaydevice, means for transmitting a group of digit impulses to the repeater, means responsive to the first impulse received for conditioning the relay device so that the impulse: repeating relay shall repeat 1 the subsequent digit impulses, and means for operating the impulse repeating relay responsive to the restoration of the relay device to transmitan impulse corresponding to the first impulse received.

6* In a telephone system, an impulse repeater. including an impulse repeating relay anda relay device, means'for transmitting a group of digit impulses to the repeater, means for operating the relay device during the transmission of, the digit impulses, means controlled by the relay device for causing the impulse repeating relay to repeat, the 1mpulses subsequent to the first i1npulse, and means for again operating the impulse repeating relay responsive to the restoration of the relay device upon the cessation of the transmission of digit impulses to transmit another impulse.

7. In a telephone system, a device for repeating a groupo-f impulses, means in said device for always adding an additional 1mpulse to the group repeated, and an outgoing loop circuit over which both the repeated impulses and the additional impulse are transmitted.

8. In a telephone system, aselector having a trunk line extending thereto, means for selecting said trunk line, the selection of said trunk causing an impulse to be automatically transmitted to said selector to prepare it to operate ina certain manner, and means for transmitting additional predetermined mpulses over said trunk to cause the operation of said selector.

9. In a telephone system, means for transmitting a predetermined number of impulses, means for receiving said impulses, and means for automatically transmitting an impulse in advance of said predetermined impulses for preparing said receiving means to respondto said predetermined impulses.

10-. In a telephone system, means for transmitting a predetermined number of impulses,

impulses to prepare said receiving means to function in response tosald predeterm ned impulses, the manner in which said receiving impulse of the repeated series of impulses,

- 12."I11- an impulse repeater for receiving and retransmitting a series of evenly spaced digit impulses, means responsive'to the seizure of'the repeater for transmitting a preliminary impulse, andmeans responsive to 'the receipt of the first impulse, of aseries for rendering the repeater 'efi'ective to retransmit the subsequent impulses of the series. q

i 13. In an'impulse repeater for receiving a series of digit impulses over any one of a plurality ofp'aths and for retransmitting a similar series of impulses, means responsive to the seizure of the repeater over one path for transmitting one preliminary impulse, means responsive to the'sei'z'u're'of the repeater over another path for transmitting a plurality of prelimii'iary impulses, and means responsive to the'receipt of the-first impulse of the series for rendering the repeater efiective to retrans- I mit the subsequent impulses of the series.

"14; In an impulse repeater, an impulse ireceiving'rel'ay, an impulse repeating relay, 'and'means responsive to the'receipt of the 1 first impulse of a seriesfor rendering said repeating relay effective to repeat subsequent impulses of the series coincidentally with f .their re'ceiptby'the receiving relay.

I 15.' In an impulse repeater, 'a{relay adapted to respond to each impulse of a series, a second relay controlled by said first relay for repeating said impulses except the first of the series, and means forcausingsaid second relay to transmit an additional impulse following the last'impulse repeated.

' 16. In a telephone system, a trunk line comprising two'sections, a relayadapted to respond to impulses transmitted over the first section of the trunkline,a second relay controlled by said first relay for transmitting cor-.

responding impulses over the second section of the trunk line, and meansfor delaying the effective action of the second relay for a period of time equal to'the duration of a comv ple'te impulse cycle.

17 In a telephone system, a trunk line comprising two sections, a relay adapted to respond to each impulse of a series received over the 'first section 'of the trunk line, a second relay controlled by said first relay for transmittingfa similar series'of impulses over the second section of the. trunk line; and means for displacing the transmitted series line in series coincident with the receipt of such impulses- 19. In an impulse repeater terminating a two conductor trunk line, means for receiving a group of d1g1t impulses and for transmitting a similar group of impulses over the two conductors of the trunk line in series, and means for delaying the retransmission of im-, pulses until and dependent upon the receipt f the secondimpulse of the group.

20. In 'an' impulse repeater terminating a two conductor trunk line, means for receiving a group of digit impulsesand for transmitting a similar-group of impulses over the two conductors of the trunk linein series, and

means for displacing the transmitted group of impulses with respect to the received group -so, that the first transmitted impulse corresponds to the second received impulse;

'21. In a repeater terminating a'trunk line comprising two talking conductors, means for receiving a group of digit impulses, means for cancelling the first impulse'of the group and for repeating subsequent impulses of the group over'the two talking conductors of'the trunk line in series, and means for transmitting an additional impulse over the trunk line followingthe last impulse repeated. I

22In a telephone system, an incoming trunk line and an outgoing trunk line each comprising two talking conductors, an impulse repeater connecting said trunk'lines, means fortransmitting a group of digit impulses over one conductor of the incoming trunk line, and means in the repeater for cancelling the first impulse of said group and for repeating subsequent impulses of the group over the two conductors of the outgoing trunk line in series.

23. In a telephone system, an incoming trunk line and an outgoing trunk line each comprising two talking conductors, an impulse repeaterconnecting said trunk lines,

' transmitting an additional impulse over the outgoing trunk line following the last repeated impulse.

24. In a repeateradapted to respond to a series of direct current impulses, means for transmitting a corresponding'seri'es ofalternating current impulses, and means for delaying the transmission of impulses until and dependent upon the receipt of the second direct current impulse.

25. In a repeater adapted to respond to a series of direct current impulses, means for transmitting a series of alternating current impulses, and means responsive to the first direct'current impulse of the series for adapting said first means to be controlled by subsequent direct current impulses of the series.

In Witness whereof, I hereunto subscribe 7 my name this 1st day of August, A. D. 1927.

MAXIMILIAN MATHIAS. 

